On Wed, Mar 06, 2024 at 10:55:00AM +0100, Alexander Stein wrote:
> Hi Frank,
>
> thanks for the patch.
>
> Am Montag, 4. März 2024, 05:32:53 CET schrieb Frank Li:
> > From: Nicolin Chen <b42378@xxxxxxxxxxxxx>
> >
> > Allocate memory from SoC internal SRAM to reduce DDR access and keep DDR in
> > lower power state (such as self-referesh) longer.
> >
> > Check iram_pool before sdma_init() so that ccb/context could be allocated
> > from iram because DDR maybe in self-referesh in lower power audio case
> > while sdma still running.
> >
> > Reviewed-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
> > Signed-off-by: Nicolin Chen <b42378@xxxxxxxxxxxxx>
> > Signed-off-by: Joy Zou <joy.zou@xxxxxxx>
> > Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
> > ---
> > drivers/dma/imx-sdma.c | 53 +++++++++++++++++++++++++++++++++++++-------------
> > 1 file changed, 40 insertions(+), 13 deletions(-)
> >
> > diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
> > index 9b42f5e96b1e0..9a6d8f1e9ff63 100644
> > --- a/drivers/dma/imx-sdma.c
> > +++ b/drivers/dma/imx-sdma.c
> > @@ -24,6 +24,7 @@
> > #include <linux/semaphore.h>
> > #include <linux/spinlock.h>
> > #include <linux/device.h>
> > +#include <linux/genalloc.h>
> > #include <linux/dma-mapping.h>
> > #include <linux/firmware.h>
> > #include <linux/slab.h>
> > @@ -516,6 +517,7 @@ struct sdma_engine {
> > void __iomem *regs;
> > struct sdma_context_data *context;
> > dma_addr_t context_phys;
> > + dma_addr_t ccb_phys;
> > struct dma_device dma_device;
> > struct clk *clk_ipg;
> > struct clk *clk_ahb;
> > @@ -531,6 +533,7 @@ struct sdma_engine {
> > /* clock ratio for AHB:SDMA core. 1:1 is 1, 2:1 is 0*/
> > bool clk_ratio;
> > bool fw_loaded;
> > + struct gen_pool *iram_pool;
> > };
> >
> > static int sdma_config_write(struct dma_chan *chan,
> > @@ -1358,8 +1361,14 @@ static int sdma_request_channel0(struct sdma_engine *sdma)
> > {
> > int ret = -EBUSY;
> >
> > - sdma->bd0 = dma_alloc_coherent(sdma->dev, PAGE_SIZE, &sdma->bd0_phys,
> > - GFP_NOWAIT);
> > + if (sdma->iram_pool)
> > + sdma->bd0 = gen_pool_dma_alloc(sdma->iram_pool,
> > + sizeof(struct sdma_buffer_descriptor),
> > + &sdma->bd0_phys);
> > + else
> > + sdma->bd0 = dma_alloc_coherent(sdma->dev,
> > + sizeof(struct sdma_buffer_descriptor),
> > + &sdma->bd0_phys, GFP_NOWAIT);
> > if (!sdma->bd0) {
> > ret = -ENOMEM;
> > goto out;
> > @@ -1379,10 +1388,14 @@ static int sdma_request_channel0(struct sdma_engine *sdma)
> > static int sdma_alloc_bd(struct sdma_desc *desc)
> > {
> > u32 bd_size = desc->num_bd * sizeof(struct sdma_buffer_descriptor);
> > + struct sdma_engine *sdma = desc->sdmac->sdma;
> > int ret = 0;
> >
> > - desc->bd = dma_alloc_coherent(desc->sdmac->sdma->dev, bd_size,
> > - &desc->bd_phys, GFP_NOWAIT);
> > + if (sdma->iram_pool)
> > + desc->bd = gen_pool_dma_alloc(sdma->iram_pool, bd_size, &desc->bd_phys);
> > + else
> > + desc->bd = dma_alloc_coherent(sdma->dev, bd_size, &desc->bd_phys, GFP_NOWAIT);
> > +
> > if (!desc->bd) {
> > ret = -ENOMEM;
> > goto out;
> > @@ -1394,9 +1407,12 @@ static int sdma_alloc_bd(struct sdma_desc *desc)
> > static void sdma_free_bd(struct sdma_desc *desc)
> > {
> > u32 bd_size = desc->num_bd * sizeof(struct sdma_buffer_descriptor);
> > + struct sdma_engine *sdma = desc->sdmac->sdma;
> >
> > - dma_free_coherent(desc->sdmac->sdma->dev, bd_size, desc->bd,
> > - desc->bd_phys);
> > + if (sdma->iram_pool)
> > + gen_pool_free(sdma->iram_pool, (unsigned long)desc->bd, bd_size);
> > + else
> > + dma_free_coherent(desc->sdmac->sdma->dev, bd_size, desc->bd, desc->bd_phys);
> > }
> >
> > static void sdma_desc_free(struct virt_dma_desc *vd)
> > @@ -2066,8 +2082,8 @@ static int sdma_get_firmware(struct sdma_engine *sdma,
> >
> > static int sdma_init(struct sdma_engine *sdma)
> > {
> > + int ccbsize;
> > int i, ret;
> > - dma_addr_t ccb_phys;
>
> What is the motivation to put ccb_phys to struct sdma_engine? AFAICS
> this is only used in sdma_init. Also the following patches of this series
> are not using the struct member.
You are right. let me check other donwstream patches. If no one use it, it
should be local variable.
>
> Best regards,
> Alexander
>
> >
> > ret = clk_enable(sdma->clk_ipg);
> > if (ret)
> > @@ -2083,10 +2099,15 @@ static int sdma_init(struct sdma_engine *sdma)
> > /* Be sure SDMA has not started yet */
> > writel_relaxed(0, sdma->regs + SDMA_H_C0PTR);
> >
> > - sdma->channel_control = dma_alloc_coherent(sdma->dev,
> > - MAX_DMA_CHANNELS * sizeof(struct sdma_channel_control) +
> > - sizeof(struct sdma_context_data),
> > - &ccb_phys, GFP_KERNEL);
> > + ccbsize = MAX_DMA_CHANNELS * (sizeof(struct sdma_channel_control)
> > + + sizeof(struct sdma_context_data));
> > +
> > + if (sdma->iram_pool)
> > + sdma->channel_control = gen_pool_dma_alloc(sdma->iram_pool,
> > + ccbsize, &sdma->ccb_phys);
> > + else
> > + sdma->channel_control = dma_alloc_coherent(sdma->dev, ccbsize, &sdma->ccb_phys,
> > + GFP_KERNEL);
> >
> > if (!sdma->channel_control) {
> > ret = -ENOMEM;
> > @@ -2095,7 +2116,7 @@ static int sdma_init(struct sdma_engine *sdma)
> >
> > sdma->context = (void *)sdma->channel_control +
> > MAX_DMA_CHANNELS * sizeof(struct sdma_channel_control);
> > - sdma->context_phys = ccb_phys +
> > + sdma->context_phys = sdma->ccb_phys +
> > MAX_DMA_CHANNELS * sizeof(struct sdma_channel_control);
> >
> > /* disable all channels */
> > @@ -2121,7 +2142,7 @@ static int sdma_init(struct sdma_engine *sdma)
> > else
> > writel_relaxed(0, sdma->regs + SDMA_H_CONFIG);
> >
> > - writel_relaxed(ccb_phys, sdma->regs + SDMA_H_C0PTR);
> > + writel_relaxed(sdma->ccb_phys, sdma->regs + SDMA_H_C0PTR);
> >
> > /* Initializes channel's priorities */
> > sdma_set_channel_priority(&sdma->channel[0], 7);
> > @@ -2272,6 +2293,12 @@ static int sdma_probe(struct platform_device *pdev)
> > vchan_init(&sdmac->vc, &sdma->dma_device);
> > }
> >
> > + if (np) {
> > + sdma->iram_pool = of_gen_pool_get(np, "iram", 0);
> > + if (sdma->iram_pool)
> > + dev_info(&pdev->dev, "alloc bd from iram.\n");
> > + }
> > +
> > ret = sdma_init(sdma);
> > if (ret)
> > goto err_init;
> >
> >
>
>
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